In 2014, over 230,000 American women were diagnosed with breast cancer (BCa), and nearly half will undergo adjuvant radiotherapy (RT). Although BCa RT increases disease-free survival and life expectancy, it is not without side-effects, primarily fatigue. Fatigue is the most prevalent symptom during BCa RT and it continues for months afterwards, having pervasive and detrimental effects on numerous aspects of patients' functioning and quality of life. Fatigue management, specifically cognitive-behavioral approaches, is recommended by the National Comprehensive Cancer Network and the American Society of Clinical Oncology. To address the important clinical and public health implications of BCa RT-related fatigue, our group developed and tested a brief Cognitive-Behavioral Therapy (CBT) intervention incorporating Hypnosis (CBTH) in two randomized controlled trials. Results revealed that CBTH managed RT-related fatigue in BCa patients during RT and for up to six months afterwards. Objectives: The goal of the proposed R25E is to train psychosocial cancer care providers in CBTH, giving them a new weapon in their fight against BCa RT-related fatigue. The Specific Aims are to: 1) Develop and implement a blended training program to teach psychosocial cancer care providers how to deliver CBTH to manage RT-related fatigue in BCa patients; 2) Evaluate the effectiveness of a CBTH training program on psychosocial cancer care providers' CBTH knowledge, skills, and real world clinical practice; and, 3) Identify trainee characteristics which predict CBTH knowledge, skills, and real world practice. The CBTH training content is guided by Roth & Philing's CBT competency model. Training will focus on the following competency domains: 1) CBTH theory and guiding principles; 2) Practical CBTH competencies (e.g., how to conduct CBT and Hypnosis); 3) Clinical and biological aspects of RT-related fatigue; 4) CBTH for fatigue in BCa RT patients; and, 5) Metacompetencies (e.g., therapeutic alliance, expectancies, empathy, cultural factors). The evaluation plan for the CBTH training program is guided by Miller's pyramid of clinical competencies, and will focus on three levels of evaluation: Knowledge and Practical Understanding, Skills, and Clinical Practice. Methods: Licensed psychosocial cancer care providers (N=400; including nurses, social workers, psychologists, and psychiatrists) from across the country will be recruited via professional organizations, listservs, and conferences. Trainees will participate in a blended training program including multimedia E-Learning and a 3-day live workshop, with evaluations linked to each modality. Trainees will also be evaluated at 3 and 6 months following the workshop. The training program will be disseminated through advocacy and professional organizations. Long-term goals: The proposed R25E is a critical first step toward improving quality of care and quality of life for BCa patients undergoing RT by producing a large cohort of psychosocial cancer care providers who are CBTH competent. Connection to NCI mission: This project is consistent with the Healthy People 2020 goal of improving quality of life of cancer patients and survivors.